[U-Boot] powerpc/mpc85xx: Increase image size

[York Sun <yorksun@freescale.com>]

On 10/16/2013 01:29 PM, Scott Wood wrote:
> On Wed, 2013-10-16 at 13:22 -0700, York Sun wrote:
>> On 10/16/2013 12:37 PM, Scott Wood wrote:
>>> On Wed, 2013-10-16 at 10:41 -0700, York Sun wrote:
>>>> On 10/11/2013 11:56 AM, York Sun wrote:
>>>>> On 10/11/2013 11:39 AM, Scott Wood wrote:
>>>>>> On Fri, 2013-10-11 at 11:29 -0700, York Sun wrote:
>>>>>>> Scott, et al.
>>>>>>>
>>>>>>> I'd like to start the discussion to increase u-boot image size for some
>>>>>>> mpc85xx targets. As we all know the reset vector is at the very end and
>>>>>>> linking process start from the top. This gives us no good choice but to
>>>>>>> use fixed image size. While we have more and more features, the size
>>>>>>> increases inevitably. It's time to adjust the arbitrary size. We are now
>>>>>>> using 512KB. Shall we go with 768KB, or even 1MB?
>>>>>>
>>>>>> 768K would affect fewer existing partition maps (many of which leave 1M
>>>>>> for U-Boot and environment combined), but 1M might be better for new
>>>>>> boards.  And of course it would be nice if someone could spare some time
>>>>>> to try to slim things down (finer-grained compile-time config,
>>>>>> speed/size tradeoffs, etc).
>>>>>>
>>>>>>> For the first step, I think we don't have to increase size for all
>>>>>>> targets. We can adjust those with CONFIG_SYS_TEXT_BASE=0xeff80000. Those
>>>>>>> are the most recent used. There are other targets which don't use NOR
>>>>>>> flash boot method. They should be considered as well.
>>>>>>>
>>>>>>> It is per board configuration. But it may be better if we keep them
>>>>>>> consistent.
>>>>>>
>>>>>> I don't think it's worth trying to keep them consistent.  Leave alone
>>>>>> old boards that are not pushing the limit, and where testing and user
>>>>>> education would be a hassle, and let newer boards where more features
>>>>>> are wanted not be constrained by the past.
>>>>>>
>>>>>
>>>>> I did a quick search for eff80000. Only these boards have it
>>>>>
>>>>> include/configs/B4860QDS.h
>>>>> include/configs/C29XPCIE.h
>>>>> include/configs/corenet_ds.h
>>>>> include/configs/HWW1U1A.h
>>>>> include/configs/MPC8536DS.h
>>>>> include/configs/MPC8572DS.h
>>>>> include/configs/P1010RDB.h
>>>>> include/configs/P1022DS.h
>>>>> include/configs/P1023RDB.h
>>>>> include/configs/P1023RDS.h
>>>>> include/configs/P1_P2_RDB.h
>>>>> include/configs/p1_p2_rdb_pc.h
>>>>> include/configs/p1_twr.h
>>>>> include/configs/P2020DS.h
>>>>> include/configs/P2041RDB.h
>>>>> include/configs/T1040QDS.h
>>>>> include/configs/t4qds.h
>>>>>
>>>>
>>>> Scott,
>>>>
>>>> Are SPL and TPL boot methods immune from the size issue here?
>>>
>>> Sort of.  We still need to fit inside existing partition tables.
>>>
>>
>> PBL boot will be broken if the image size is bigger than 512KB, right?
> 
> It has to be even smaller than that, to make room for early data.
> 

So if we go with 768KB, do we have to convert all PBL boot to SPL boot?

York